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<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>ceshi</title>
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    <script>
      is_weixn();
      function is_weixn() {
        var ua = navigator.userAgent.toLowerCase();

        if (ua.match(/MicroMessenger/i) == "micromessenger") {
          alert("true");
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          alert("false");
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